Quote Originally Posted by RezDog View Post
From my limited experience of ordering the knots too big the last time, 2mm less than your hole size. They sort of balloon out just above the base. 2mm smaller is actually a tight fit.
I can confirm this, always make sure your knot hole is bigger than the knot it self. not only do they balloon out as RezDog said, it wil also help with splaying the knot as you use it. I usualy take 1-2 mm bigger on the smaller knot, and i go 2-3 mm bigger on the big knots (think 28-30 mm) this depends on what knot you want to use, the lower cost knots normally have a bigger glue bump so they need a bigger hole than the higher cost ones.